Good lubricant for leather/plastic??

[07TahoeLTZ]

I have been chasing a creaking sound for weaks now and finally got it...it is where the driver side arm rest (where your elbow would sit) and the plastic door panel come together. If you press down on the arm rest just slightly, you can hear the creak..whenever I hit 'chatter' bumps, this creak kills me!!! There are plenty of little crevices and cracks I would spray some type of lubricant in using a little hose (like on WD40 bottles). Any suggestions???

If a lubricant doesn't work, anyone have a schematic of how to get the door trim panels off around the armrest?

Thanks!!!!!